U.S. patent number 11,118,867 [Application Number 16/728,324] was granted by the patent office on 2021-09-14 for interactive weapon targeting system displaying remote sensed image of target area.
This patent grant is currently assigned to AEROVIRONMENT, INC.. The grantee listed for this patent is AeroVironment, Inc.. Invention is credited to Earl Clyde Cox, John C. McNeil, Jon Andrew Ross, Makoto Ueno.
United States Patent |
11,118,867 |
McNeil , et al. |
September 14, 2021 |
Interactive weapon targeting system displaying remote sensed image
of target area
Abstract
Systems, devices, and methods for determining a predicted impact
point of a selected weapon and associated round based on stored
ballistic information, provided elevation data, provided azimuth
data, and provided position data.
Inventors: |
McNeil; John C. (Tujunga,
CA), Cox; Earl Clyde (La Cresenta, CA), Ueno; Makoto
(Simi Valley, CA), Ross; Jon Andrew (Moorpark, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
AeroVironment, Inc. |
Simi Valley |
CA |
US |
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Assignee: |
AEROVIRONMENT, INC. (Arlington,
VA)
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Family
ID: |
1000005801152 |
Appl.
No.: |
16/728,324 |
Filed: |
December 27, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200326156 A1 |
Oct 15, 2020 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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16279876 |
Feb 19, 2019 |
10539394 |
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15730250 |
Apr 2, 2019 |
10247518 |
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14530486 |
Nov 14, 2017 |
9816785 |
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61898342 |
Oct 31, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41G
5/14 (20130101); F41G 3/142 (20130101); F41G
3/165 (20130101); F41G 3/02 (20130101) |
Current International
Class: |
F41G
5/14 (20060101); F41G 3/02 (20060101); F41G
3/14 (20060101); F41G 3/16 (20060101) |
Field of
Search: |
;89/41.05,41.01,41.03,41.18,41.21,203 ;235/407 ;348/144 ;244/63
;701/2,501 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
International Search Report for PCT/US14/63537, dated Mar. 11,
2015. cited by applicant .
Li Bing, Liu Rongyuan, Liu Suhong, etal. Monitoring vegetation
coverage variation of winter wheat by low-altitude UAVremotesensing
system[J]. Transactions of the Chinese Society of Agricultural
Engineering (Transactions of the CSAE), 2012, 28(13):160-165. (in
Chinese with English abstract). cited by applicant .
Written Opinion for Singapore Application No. 11201603140W dated
Mar. 1, 2017. cited by applicant .
Document received of "Potential Prior Art for AV" on Dec. 9, 2020.
cited by applicant.
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Primary Examiner: Cooper; John
Attorney, Agent or Firm: Concept IP LLP Yedidsion; Pejman
Aagaard; Eric
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. Non-Provisional patent
application Ser. No. 16/279,876 filed Feb. 19, 2019, which is a
continuation of U.S. Non-Provisional patent application Ser. No.
15/730,250 filed Oct. 11, 2017, which issued as U.S. Pat. No.
10,247,518 on Apr. 2, 2019, which is a continuation of U.S.
Non-Provisional patent application Ser. No. 14/530,486 filed Oct.
31, 2014, which issued as U.S. Pat. No. 9,816,785 on Nov. 14, 2017,
which claims priority to and the benefit of U.S. Provisional Patent
Application No. 61/898,342, filed Oct. 31, 2013, the contents of
all of which are hereby incorporated by reference herein for all
purposes.
Claims
What is claimed is:
1. A system, comprising: a weapon of one or more weapons, wherein
each weapon of the one or more weapons has a weapon display; one or
more remote sensors associated with one or more aerial vehicles,
wherein at least one remote sensor is configured to provide image
metadata of a predicted impact point to the weapon display; one or
more sensor controllers on each of the one or more aerial vehicles
configured to direct pointing of the one or more remote sensors;
and a targeting device comprising: a fire control controller,
wherein the fire control controller determines a predicted impact
point of the one or more weapons and an associated round, and
wherein the fire control controller transmits information on the
predicted impact point to the one or more sensor controllers to
direct pointing of at least one remote sensor of at least one
aerial vehicle.
2. The system of claim 1, wherein the targeting device further
comprises: a data store having ballistic information associated
with the weapon of the one or more weapons and associated
rounds.
3. The system of claim 1, wherein the fire control controller
determines the predicted impact point of the one or more weapons
based on at least one of: the ballistic information, elevation data
received from an inertial measurement unit, azimuth data received
from a magnetic compass, and position data received from a position
determining component.
4. The system of claim 3 wherein: the inertial measurement unit is
in communication with the fire control controller; the magnetic
compass is in communication with the fire control controller; and
the position determining component is in communication with the
fire control controller.
5. The system of claim 3, wherein the position determining
component is a navigation unit.
6. The system of claim 1, wherein the fire control controller
determines the predicted impact point of the one or more weapons
based on the ballistic information, elevation data received from an
inertial measurement unit, azimuth data received from a magnetic
compass, and position data received from a position determining
component.
7. The system of claim 1 further comprising: a radio frequency (RF)
receiver, wherein the information on the predicted impact point
transmitted by the fire control controller is received by the RF
receiver.
8. The system of claim 1, wherein the one or more aerial vehicles
is an unmanned aerial vehicle (UAV).
9. The system of claim 1, wherein the targeting device determines a
position and orientation of the one or more weapons and further
uses a ballistic lookup table to determine the predicted impact
point of the weapon of the plurality of weapons.
10. The system of claim 1, wherein the remote sensor is an optical
camera.
11. The system of claim 10, wherein the optical camera is
configured to provide video images for display on the weapon
display.
12. The system of claim 1 further comprising: an environmental
condition determiner configured to provide information related to
environmental conditions of the surrounding areas of the predicted
impact point in order for the fire control controller to determine
the predicted impact point.
13. The system of claim 1 further comprising: a ballistic range
determiner in communication with the fire control controller,
wherein the ballistic range determiner is configured to determine
the predicted impact point based on the weapon position, azimuth,
elevation, and round type.
14. The system of claim 1, wherein the fire control controller
receives image metadata from the one or more remote sensors, and
wherein the image metadata comprises a ground position of a Center
Field of View (CFOV) of the remote sensor.
15. The system of claim 14, wherein the CFOV is directed at the
determined predicted impact point.
Description
TECHNICAL FIELD
Embodiments relate generally to systems, methods, and devices for
weapon systems and Unmanned Aerial Systems (UAS), and more
particularly to displaying remote sensed images of a target area
for interactive weapon targeting.
BACKGROUND
Weapon targeting has typically been performed by a gun operator
firing the weapon. Weapon targeting systems and fire-control
systems for indirect fire weapons do not provide the operator with
direct view of the target.
SUMMARY
A device is disclosed that includes a fire control controller, an
inertial measurement unit in communication with the fire control
controller, the inertial measurement unit configured to provide
elevation data to the fire control controller, a magnetic compass
in communication with the fire control controller, the magnetic
compass operable to provide azimuth data to the fire control
controller, a navigation unit in communication with the fire
control controller, the navigation unit configured to provide
position data to the fire control controller, and a data store in
communication with the fire control controller, the data store
having ballistic information associated with a plurality of weapons
and associated rounds, so that the fire control controller
determines a predicted impact point of a selected weapon and
associated round based on the stored ballistic information, the
provided elevation data, the provided azimuth data, and the
provided position data. In one embodiment, the fire control
controller may receive image metadata from a remote sensor, wherein
the image metadata may include ground position of a Center Field of
View (CFOV) of the remote sensor, and wherein the CFOV may be
directed at the determined predicted impact point. The fire control
controller may determine an icon overlay based on the received
image metadata from the remote sensor, wherein the icon overlay may
include the position of the CFOV and the determined predicted
impact point. The fire control controller may also determine the
predicted impact point based further on predicting a distance
associated with a specific weapon, wherein the distance may be the
distance between a current location of the rounds of the weapon and
a point of impact with the ground. Embodiments may also include a
map database configured to provide information related to visual
representation of terrains of an area to the fire control
controller to determine the predicted impact point and the fire
control controller may also determine the predicted impact point
based further on the map database information.
In another embodiment, the device also includes an environmental
condition determiner configured to provide information related to
environmental conditions of the surrounding areas of the predicted
impact point in order for the fire control controller to determine
the predicted impact point. In such an embodiment, the fire control
controller may determine the predicted impact point based further
on the environmental condition information so that the fire control
controller is further configured to communicate with an
electromagnetic radiation transceiver, the transceiver configured
to transmit and receive electromagnetic radiation. The
electromagnetic radiation transceiver may be a radio frequency (RF)
receiver and RF transmitter. In an alternative embodiment, the
electromagnetic radiation transceiver may be further configured to
receive video content and image metadata from a remote sensor, and
the remote sensor may transmit the image metadata via a
communication device of a sensor controller on an aerial vehicle
housing the remote sensor. The remote sensor may be mounted to the
aerial vehicle, and the electromagnetic radiation transceiver may
be further configured to transmit information to the sensor
controller of the aerial vehicle. The fire control controller may
transmit information that includes the determined predicted impact
point to the sensor controller of the aerial vehicle to direct the
pointing of the remote sensor mounted to the aerial vehicle.
In other embodiments, a ballistic range determiner may be
configured to determine the predicted impact point based on the
weapon position, azimuth, elevation, and round type. Also, the data
store may be a database, the database including at least one of a
lookup table, one or more algorithms, and a combination of a lookup
table and one or more algorithms. The position determining
component may also include at least one of: a terrestrially based
position determining component; a satellite based position
determining component; and a hybrid of terrestrially and satellite
based position determining devices. The fire control controller is
in communication with a user interface, the user interface
including at least one of: a tactile responsive component; an
electromechanical radiation responsive component; and an
electromagnetic radiation responsive component, and the user
interface may be configured to: receive a set of instructions via
the user interface and transmit the received set of instructions to
the fire control controller.
In another embodiment, the device may also include an instruction
creating component having at least one of a user interface
configured to identify and record select predefined activity
occurring at the user interface, and a communication interface in
communication with a remote communication device, the remote
communication device configured to direct a remote sensor via a
sensor controller; so that a user at the user interface requests
the remote sensor to aim at an anticipated weapon targeting
location. The instruction creating component may be in
communication with an aerial vehicle housing the remote sensor to
transmit instructions to the aerial vehicle to keep a weapon
targeting location in the view of the remote sensor.
A remote targeting system is also disclosed that includes a weapon,
a display on the weapon, a radio frequency (RF) receiver, a sensor
remote from the weapon, wherein the sensor is configured to provide
image metadata of a predicted impact point on the weapon display,
and a targeting device that itself includes a data store having
ballistic information associated with a plurality of weapons and
associated rounds and a fire control controller wherein the fire
control controller determines a predicted impact point based on the
ballistic information, elevation data received from an inertial
measurement unit, azimuth data received from a magnetic compass,
position data received from a position determining component,
wherein the fire control controller is in communication with the
inertial measurement unit, the magnetic compass, and the position
determining component. The remote sensor may be mounted to an
unmanned aerial vehicle. The targeting system may determine a
position and orientation of the weapon and further uses a ballistic
lookup table to determine the predicted impact point of the weapon.
The remote sensor may receive the predicted impact point of the
weapon and aim the sensor at the predicted impact point of the
weapon. The system further may also include a second weapon, a
second display on the second weapon, and a second targeting device,
so that the predicted impact point on the weapon display provided
by the remote sensor is the same as the predicted image location on
the second weapon display. In one embodiment, the second weapon has
no control over the remote sensor. Also, the second weapon may not
send any predicted impact point information of the second weapon to
the remote sensor. The determined predicted impact point of the
weapon may be different than a determined predicted impact point of
the second weapon. The sensor may be an optical camera configured
to provide video images to the remote targeting system for display
on the weapon display.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments are illustrated by way of example and not limitation in
the figures of the accompanying drawings, and in which:
FIG. 1 is an exemplary embodiment of a weapon targeting system
environment;
FIG. 2 is an exemplary embodiment of a system that includes a
handheld or mounted gun or grenade launcher, with a mounted
computing device, and an Unmanned Aerial Vehicle (UAV) with a
remote sensor;
FIG. 3 shows a top view of a UAV with a remote sensor initially
positioned away from a target and a predicted impact point of the
weapon;
FIG. 4 is a flowchart of an exemplary embodiment of the weapon
targeting system;
FIG. 5 is a functional block diagram depicting an exemplary weapon
targeting system;
FIG. 6 shows an embodiment of the weapon targeting system having a
weapon with a display or sight which views a target area about a
predicted impact ground point (GP) and centered on a Center Field
of View;
FIG. 7 shows embodiments of the weapon targeting system where the
targeting system is configured to control the remote camera on the
UAV;
FIG. 8 shows a set of exemplary displays of an embodiment of the
weapon targeting system with passive control sensor/UAV
control;
FIG. 9 shows embodiments where the image from the remote sensor is
rotated or not rotated to the weapon user's perspective;
FIG. 10 depicts an exemplary embodiment of the weapon targeting
system that may include multiple weapons receiving imagery from one
remote sensor;
FIG. 11 depicts a scenario where as the weapon is maneuvered by the
user, the predicted impact GP of the weapon passes through
different areas; and
FIG. 12 illustrates an exemplary top level functional block diagram
of a computing device embodiment.
DETAILED DESCRIPTION
Weapon targeting systems are disclosed herein where the systems may
have a gun data computer or ballistic computer, a fire control
controller, a communication device, and optionally an
object-detection system or radar, which are all designed to aid the
weapon targeting system in hitting a determined target faster and
more accurately. The exemplary weapon targeting system embodiments
may display remote sensed images of a target area for interactive
weapon targeting and accurately aim the weapon rounds at the target
area. One embodiment may include an Unmanned Aerial System (UAS),
such as an Unmanned Aerial Vehicle (UAV). The UAV may be a fixed
wing vehicle or may have one or more propellers connected to a
chassis in order to enable the UAV to hover in a relatively
stationary position. Additionally, the UAV may include a sensor,
where the sensor is remote to the weapon targeting system, and the
sensor may be an image capture device. The sensor may be aimed so
as to have a viewing range of an area about an identified target.
The sensor on the UAV may be moved by commands received from
different origins, for example, the pilot of the UAV or a ground
operator. The sensor may also be commanded to focus on a specific
target on a continuous basis and based on direction received from a
ground operator.
In one embodiment of the weapon targeting system, the system may be
used for displaying to a user of a weapon, the weapon's target
area, e.g., an area about where the determined or calculated
weapon's impact may be, as viewed from a sensor remote from the
weapon. This allows the user to view in real-time (or near
real-time) the effect of the weapon within the target area and make
targeting adjustments to the weapon. To aid in the aiming of the
weapon, the display may indicate within the target area on the
display, a determined or anticipated impact location, using an
indicator, for example, a reticle, a crosshair, or an error
estimation ellipse/region. The use of a remote sensor may allow
targets to be engaged without a direct line of sight from the user
to the target, for example, when the target is located behind an
obstruction, such as a hill. The remote sensor may be any of a
variety of known sensors which may be carried by a variety of
platforms. In some embodiments, the sensor may be a camera mounted
to an air vehicle that is positioned away from the weapon and
within viewing range of the area about the target. Such an air
vehicle may be a UAV such as a small unmanned aerial system
(SUAS).
FIG. 1 depicts a weapon targeting system environment 100 having a
weapon 110, a display 120, a targeting device 130, a communication
device 140, a remote sensor 150, a remote communication device 160,
and a sensor controller 170. Also shown is a target A, an
anticipated weapon effect or predicted targeting location B, the
viewed target area C, and the actual weapon effect D. The weapon
targeting system environment 100 may also include a set of
obstructions, such as hills, a weapon mount for rotating the
weapon, and an aerial vehicle 180 where the remote sensor 150, the
remote communication device 160, and the sensor controller 170 may
be mounted to.
The weapon 110 may be any of a variety of weapons, such as a
grenade launcher, a mortar, an artillery gun, tank gun, ship gun,
deck gun, or any other weapon that launches a projectile to impact
a location of weapon effect. In some embodiments, the weapon 110
may be moving in order to allow it to be easily moved along with
the gun and rounds associated with the weapon. The targeting device
130 may include an inertial measuring unit (IMU) that may include
magnetometers, gyroscopes, accelerometers, as well as a magnetic
compass and a navigation system, which may be a global positioning
system (GPS), to determine the location and orientation of the
weapon 110. As a user maneuvers or positions the weapon 110, the
targeting device 130 may monitor the weapon's location thereby
determining the direction the weapon is pointing (which may be a
compass heading), the weapon's orientation, for example, the angle
of the weapon relative to a local level parallel to the ground.
Additionally, the targeting device may then, based on
characteristics of the weapon and its projectiles, use a target
determination means 132, such as a ballistic computer, lookup
table, or the like, to provide a determined point of weapon effect.
The point of weapon effect may be the expected projectile impact
point, which may be an anticipated weapon effect location. The
target determination means 132 may also reference a database or a
map with elevation information to allow for a more accurate
determination of the weapon effect or predicted targeting location
B. The targeting location information may include longitude,
latitude, and elevation of the location and may further include
error values, such as weather conditions, about or near the
targeting location.
In embodiments, the targeting device 130 may, for example, be a
tablet computer having an inertial measurement unit, such as a
Nexus 7 available from Samsung Group of Samsung Town, Seoul, South
Korea (via Samsung Electronics of America, Ridgefield Park, N.J.),
an iPad, available from Apple, Inc. of Cupertino, Calif., or a
Nexus 7, available from ASUSTeK Computer Inc. of Taipei, Taiwan
(via ASUS Fremont, Calif.).
The targeting location information relating to the targeting
location B may then be sent, via the communication device 140, to
the remote communication device 160 connected to the sensor
controller 170, where the sensor controller 170 may direct the
remote sensor 150. In one embodiment, the communication device 140
may send targeting information to the UAV Ground Control Station
via the remote communication device 160, then the UAV Ground
Control Station may send the targeting information back to the
remote communication device 160 that may then forward it to the
sensor controller 170. The remote sensor 150 may then be aimed to
view the anticipated weapon targeting location B, which may include
the adjacent areas around this location. The adjacent areas around
this location are depicted in FIG. 1 as the viewed target area
C.
The control for aiming of the remote sensor 150 may be determined
by the sensor controller 170, where the sensor controller 170 may
have a processor and addressable memory, and which may utilize the
location of the remote sensor 150, the orientation of the remote
sensor 150--namely its compass direction--and the angle relative to
level to determine where on the ground the sensor is aimed, which
could be the image center, image boundary, or both the image center
and image boundary. In one embodiment, the location of the remote
sensor 150 may optionally be obtained from the UAV's onboard GPS
sensors. In another embodiment, the orientation of the sensor, for
example, compass direction and angle relative to level, may be
determined by the orientation and angle to level of the UAV and the
orientation and angle of the sensor relative to the UAV. In some
embodiments, the sensor controller 170 may aim the sensor to the
anticipated weapon targeting location B, and/or the viewed target
area C. Optionally, the aiming of the remote sensor 150 by the
sensor controller 170 may include the zooming of the sensor.
In embodiments, the communication device 140 may be connected to a
Ground Control Station (GCS), for example, one available from
AeroVironment, Inc. of Monrovia Calif.
(http://www.avinc.com/uas/small_uas/gcs/) and may include a Digital
Data Link (DDL) Transceiver bi-directional, digital, wireless data
link, for example, available from AeroVironment, Inc. of Monrovia
Calif. (http://www.avinc.com/uas/ddl/).
In some embodiments, the remote communication device 160 and the
remote sensor 150 may be mounted on a flying machine, such as
satellites or an aerial vehicle, whether manned aerial vehicle or
unmanned aerial vehicle (UAV) 180 flying within viewing distance of
the target area C. The UAV 180 may be any of a variety of known air
vehicles, such as a fixed wing aircraft, a helicopter, a quadrotor,
blimp, tethered balloon, or the like. The UAV 180 may include a
location determining device 182, such as a GPS module and an
orientation or direction determining device 184, such as an IMU
and/or compass. The GPS 182 and the IMU 184, provide data to a
control system 186 to determine the UAV's position and orientation,
which in turn may be used with the anticipated weapon targeting
location B to direct the remote sensor 150 to view the location B.
In some embodiments, the sensor controller 170 may move, i.e.,
tilt, pan, zoom, the remote sensor 150 based on the received data
from the control system 186 and the anticipated weapon targeting
location received from the weapon targeting system.
In one embodiment, either the IMU 184 or the control system 186 may
determine the attitude, i.e., pitch, roll, yaw, position, and
heading, of the UAV 180. Once the determination is made, the IMU
184 (or system 186) using an input of Digital Terrain and Elevation
Data (DTED) (stored on board the UAV in a data store, e.g., a
database), may then determine where any particular earth-referenced
grid position is located (such as location B), relative to a
reference on the UAV, such as its hull. In this embodiment, this
information may then be used by the sensor controller 170 to
position the remote sensor 150 to aim at a desired targeting
location relative to the UAV's hull.
In addition to pointing the camera at the targeting location B, if
permitted by the operator of the UAV (VO), the UAV may also attempt
to center an orbit on the targeting location B. The VO will ideally
specify a safe air volume in which the UAV may safely fly based
upon locations specified by the display on the gun. In some
embodiments, the system may enable a gun operator to specify a
desired `Stare From` location for the UAV to fly if the actual
location is not the desired targeting location to center the UAV's
orbit. Additionally, the safe air volume may be determined based on
receiving geographic data defining a selected geographical area and
optionally, an operating mode associated with the selected
geographical area, where the received operating mode may restrict
flight by the UAV over an air volume that may be outside the safe
air volume. That is, the VO may control the flight of the UAV based
on the selected geographical area and the received operating mode.
Accordingly, in one embodiment the weapon operator may be able to
fully control the UAV's operation and flight path. Additionally, a
ground operator or a pilot of the UAV may command the weapon and
direct the weapon to point to a target based on the UAV's imagery
data.
Commands from the weapon system to the UAV or to the sensor may be
sent, for example, via any command language including Cursor on
Target (CoT), STANAG 4586 (NATO Standard Interface of the Unmanned
Control System--Unmanned Aerial Vehicle interoperability), or Joint
Architecture for Unmanned Systems (JAUS).
The field of view of the remote sensor 150 may be defined as the
extent of the observable area that is captured at any given moment
in time. Accordingly, the Center Field of View (CFOV) of the sensor
150 may point at the indicated weapon targeting location B. The
user may manually zoom in or zoom out on the image of the targeting
location B to get the best view associated with the expected weapon
impact site, including the surrounding target area and the target.
The remote sensor 150 captures imagery data and the sensor
controller 170, via the remote communication device 160, may
transmit the captured data along with related metadata. The
metadata in some embodiments may include other data related to and
associated with the imagery being captured by the remote sensor
150. In one embodiment, the metadata accompanying the imagery may
indicate the actual CFOV, for example, assuming it may still be
slewing to the indicated location, as well as the actual grid
positions of each corner of the image being transmitted. This
allows the display to show where the anticipated weapon targeting
location B is on the image, and draw a reticle, e.g., crosshair, at
that location.
In some exemplary embodiments, the remote sensor 150 may be an
optical camera mounted on a gimbal such that it may pan and tilt
relative to the UAV. In other embodiments the sensor 150 may be an
optical camera mounted in a fixed position in the UAV and the UAV
is positioned to maintain the camera viewing the target area C. The
remote sensor may be equipped with either optical or digital zoom
capabilities. In one embodiment, there may be multiple cameras that
may include Infra-Red or optical wavelengths on the UAV that the
operator may optionally switch between. According to the exemplary
embodiments, the image generated by the remote sensor 150 may be
transmitted by the remote communication device 160 to a display 120
via the communication device 140. In one embodiment, data, such as
image metadata, that provides information including the CFOV and
each corner of the view as grid locations, e.g., the ground
longitude, latitude, elevation of each point, may be transmitted
with the imagery from the remote sensor 150. The display 120 may
then display to the weapon user the viewed target area C which
includes the anticipated weapon targeting location B which as shown
in FIG. 1, may be a targeting reticle, as the CFOV. In some
embodiments, the anticipated targeting location B may be shown
separate from the CFOV, such as when the weapon 110 is being moved
and the remote sensor 150 is slewing, e.g., tilting and/or yawing,
to catch up to the new location B and re-center the CFOV at the new
location. In this manner, as the user maneuvers the weapon 110,
e.g., rotates, and/or angles the weapon, the user may see on the
display 120 where the predicted targeting location B of the weapon
110 is as viewed by the remote sensor 150. This allows the weapon
user to see the targeting location--and the target and weapon
impacts--even without a direct line of sight from the weapon to the
targeting location B, such as with the target positioned behind an
obstruction.
In one embodiment, to aid the user, the image displayed may be
rotated for the display to align with the compass direction so that
the weapon is pointed or by some defined fixed direction, e.g.,
north is always up on the display. The image may be rotated to
conform to the weapon user's orientation, regardless of the
position of the UAV or other mounting of the remote sensor. In
embodiments, the orientation of the image on the display is
controlled by the bore azimuth of the gun barrel or mortar tube as
computed by the targeting device, e.g., a fire control computer. In
some embodiments, the display 120 may also show the position of the
weapon within the viewed target area C.
In embodiments, the remote communication device 160, the remote
sensor 150 and the sensor controller 170 may all be embodied, for
example, in a Shrike VTOL that is a man-packable, Vertical Take-Off
and Landing Micro Air Vehicle (VTOL MAV) system available from
AeroVironment, Inc. of Monrovia Calif.
(http://www.avinc.com/uas/small_uas/shrike/).
Additionally, some embodiments of the targeting system may include
a targeting error correction. In one exemplary embodiment, air
vehicle wind estimates may be provided as a live feed to be used
with the round impact estimates and provide more accurate error
correction. When the actual impact ground point of the weapon's
round is displaced from the predicted impact ground point (GP),
without changing the weapons position, the user on their display
may highlight the actual impact GP and the targeting system may
determine a correction value to apply to the determination of the
predicted impact GP and then provide this new predicted GP to the
remote sensor and display it on the weapon display. One embodiment
of such is shown in FIG. 1, in the display 120, where the actual
impact point D is offset from the predicted impact GP B. In this
embodiment, the user may highlight the point D and input to the
targeting system as the actual impact point which would then
provide for a targeting error correction. Accordingly, the target
impact point may be corrected via tracking the first round impact
and then adjusting the weapon on the target. In another exemplary
embodiment of the error correction or calibration, the system may
detect an impact point using image processing on the received
imagery that depicts the impact point before and upon impact. This
embodiment may determine when a declaration may be made that impact
has happened based on determining a computed time of flight
associated with the rounds used. The system may then adjust the
position based on the expected landing area for the rounds and last
actual round that was fired.
FIG. 2 depicts embodiments that include a handheld or mounted gun
or grenade launcher 210, with a mounted computing device, e.g., a
tablet computer 220, having a video display 222, an inertial
measurement unit (IMU) 230, a ballistic range module 232, a
communication module 240, and a UAV 250 with a remote sensor, e.g.,
an imaging sensor 252. The UAV 250 may further have a navigation
unit 254, e.g., GPS, and a sensor mounted on a gimbal 256 such that
the sensor 252 may pan and tilt relative to the UAV 250. The IMU
230 may use a combination of accelerometers, gyros, encoders, or
magnetometers to determine the azimuth and elevation of the weapon
210. The IMU 230 may include a hardware module in the tablet
computer 220, an independent device that measures attitude, or a
series of position sensors in the weapon mounting device. For
example, in some embodiments the IMU may use an electronic device
that measures and reports on a device's velocity, orientation, and
gravitational forces by reading the sensors of the tablet computer
220.
The ballistic range module 232 calculates the estimated or
predicted impact point given the weapon position (namely latitude,
longitude, and elevation), azimuth, elevation, and round type. In
one embodiment, the predicted impact point may be further refined
by the ballistic range module including in the calculations, wind
estimates. The ballistic range module 232 may be a module in the
tablet computer or an independent computer having a separate
processor and memory. The calculation may be done by a lookup table
constructed based on range testing of the weapon. The output of the
ballistic range module may be a series of messages including the
predicted impact point B (namely latitude, longitude, and
elevation). The ballistic range module 232 may be in the form of
non-transitory computer enabled instructions that may be downloaded
to the tablet 220 as an application program.
The communication module 240 may send the estimated or predicted
impact point to the UAV 250 over a wireless communication link,
e.g., an RF link. The communication module 240 may be a computing
device, for example, a computing device designed to withstand
vibration, drops, extreme temperature, and other rough handling.
The communication module 240 may be connected to or in
communication with a UAV ground control station, or a Pocket DDL RF
module, available from AeroVironment, Inc. of Monrovia, Calif. In
one exemplary embodiment, the impact point message may be the
"cursor-on-target" format, a geospacial grid, or other formatting
of latitude and longitude.
The UAV 250 may receive the RF message and point the imaging sensor
252--remote to the weapon--at the predicted impact point B. In one
embodiment, the imaging sensor 252 sends video over the UAV's RF
link to the communication module 240. In one exemplary embodiment,
the video and metadata may be transmitted in Motion Imagery
Standards Board (MISB) format. The communication module may then
send this video stream back to the tablet computer 220. The tablet
computer 220, with its video processor 234, rotates the video to
align with the gunner's frame of reference and adds a reticle
overlay that shows the gunner the predicted impact point B in the
video. The rotation of the video image may be done such that the
top of the image that the gunner sees matches the compass direction
that the gun 210 is pointing at, or alternatively the compass
direction determined from the gun's azimuth, or compass direction
between the target position and gun position.
In some embodiments, the video image being displayed on the video
display 222 on the tablet computer 220 provided to the user of the
weapon 210, may include the predicted impact point B and a
calculated error ellipse C. Also shown on the video image 222 is
the UAV's Center Field of View (CFOV) D.
In one embodiment, in addition to automatically directing the
sensor or camera gimbal toward the predicted impact point, the UAV
may also fly towards, or position itself about, the predicted
impact point. Flying toward the predicted impact point may occur
when the UAV is initially (upon receiving the coordinates of the
predicted impact point) at a location where the predicted impact
point is too distant to be seen, or to be seen with sufficient
resolution by the UAV's sensor. In addition, with the predicted
impact point, the UAV may automatically establish a holding
pattern, or holding position, for the UAV, where such holding
pattern/position allows the UAV sensor to be within observation
range and without obstruction. Such a holding pattern may be such
that it positions the UAV to allow a fixed side-view camera or
sensor to maintain the predicted impact point in view.
FIG. 3 shows a top view of the UAV 310 with a remote sensor 312
initially positioned away from a target 304 and the predicted
impact point B of the weapon 302, such that the image produced by
the sensor 312 of the predicted impact point B and the target area
(presumably including the target 304), as shown by the image line
320, the sensor lacks sufficient resolution to provide sufficiently
useful targeting of the weapon 302 for the user. As such, the UAV
310 may alter its course to move the sensor closer to the predicted
impact point B. This alternation of course may be automatic when
the UAV is set to follow, or be controlled by, the weapon 302, or
the course alternation may be done by the UAV operator when
requested or commanded by the weapon user. In one embodiment,
retaining control of the UAV by the UAV operator allows for
consideration of, and response to, factors such as airspace
restrictions, UAV endurance, UAV safety, task assignment, and the
like.
As shown in FIG. 3, the UAV executes a right turn and proceeds
towards the predicted impact point B. In embodiments of the weapon
targeting system, the UAV may fly to a specific location C--as
shown by course line 340--that is a distance d away from the
predicted impact point B. This move allows the sensor 312 to
properly observe the predicted impact point B and to allow for
targeting of the weapon 302 to the target 304. The distance d may
vary and may depend on a variety of factors, including the
capabilities of the sensor 312, e.g., zoom, resolution, stability,
etc., capabilities of the display screen on the weapon 302, e.g.,
resolution, etc., user abilities to utilize the imaging, as well as
factors such as how close the UAV should be positioned from the
target. In this exemplary embodiment, the UAV upon reaching the
location C may then position itself to be in a holding pattern or
observation position 350 to maintain a view of the predicted impact
point B. As shown, the holding pattern 350 is a circle about the
predicted impact point B, other patterns also be used in accordance
with these exemplary embodiments. With the UAV 310' in the holding
pattern 350, the UAV may now continuously reposition its sensor
312' to maintain its view 322 of the predicted impact point B. That
is, while the UAV is flying about the target, the sensor looks at
or is locked on the predicted impact point location. In this
embodiment, during the holding pattern time the UAV may transmit a
video image back to the weapon 302. As the user of the weapon 302
repositions the aim of the weapon, the UAV may re-aim the sensor
312' and/or reposition the UAV 310' itself to keep the new
anticipated weapon targeting location in the sensor's view. In an
exemplary embodiment, the remote sensor may optionally be viewing
the target, while guiding the weapon, so that the anticipated
targeting location coincides with the target.
FIG. 4 is a flowchart of an exemplary embodiment of the weapon
targeting system 400. The method depicted in the diagram includes
the steps of: The Weapon is placed in position, for example, by a
user (step 410); Targeting Device Determines the Anticipated Weapon
Effect Location (step 420); the Communication Device Transmits the
Anticipated Weapon Effect Location to the Remote Communication
Device (step 430); The Remote Sensor Controller Receives the Effect
Location from the Remote Communication Device and Directs the
Remote Sensor to the Effect Location (step 440); The Sensor
Transmits Imagery of the Effect Location to the Weapon Display
Screen via the Remote Communication Device and the Weapon
Communication Device (step 450); and The User Views the Anticipated
Weapon Effect Location and Target Area (may include a target) (step
460). The effect location may be the calculated, predicted, or
expected impact point with or without an error. After the step 460
the process may start over at step 410. In this manner a user may
aim the weapon and adjust the fire on to a target based on the
previous received imagery of effect location. In one embodiment,
step 450 may include rotating the image so to align the image with
the direction of the weapons to aid the user in targeting.
FIG. 5 depicts a functional block diagram of a weapon targeting
system 500 where the system includes a display 520, a targeting
device 530, a UAV remote video terminal 540, and an RF receiver
542. The display 520 and targeting device 530 may be detachably
attached or mounted on, or operating with, a gun or other weapon
(not shown). The display 520 may be visible to the user of the
weapon to facilitate targeting and directing fire. The targeting
device 530, may include a fire control controller 532, the fire
control controller having a processor and addressable memory, an
IMU 534, a magnetic compass 535, a GPS 536, and a ballistic data on
gun and round database 537. The IMU 534 generates the elevation
position, or angle from level, of the weapon and provides this
information to the fire control controller 532. The magnetic
compass 535 provides the azimuth of the weapon to the controller
532, such as the compass heading that the weapon is aimed toward.
The GPS 536 provides the location of the weapon to the fire control
controller 532, which typically includes the longitude, latitude,
and altitude (or elevation). The database 537 provides to the fire
control controller 532 ballistic information on both the weapon and
on its round (projectile). The database 537 may be a lookup table,
one or more algorithms, or both, however typically a lookup table
is provided. The fire control controller 532 may be in
communication with the IMU 534, the compass 535, the GPS 536, and
database 537.
In addition, the fire control controller 532 may use the weapon's
position and orientation information from the components IMU 534,
the compass 535, the GPS 536 to process with the weapon and round
ballistics data from the database 537 and to determine an estimated
or predicted ground impact point (not shown). In some embodiments,
the controller 532 may use the elevation of the weapon from the IMU
534 to process through a lookup table of database 537, with a
defined type of weapon and round, to determine the predicted range
or distance from the weapon the round will travel to the point of
impact with the ground. The type of weapon and round may be set by
the user of the weapon prior to the operation of the weapon, and in
embodiments, the round selection may change during the use of the
weapon. Once the distance is determined, the fire control
controller 532 may use the weapon position from the GPS 536 and the
weapon azimuth from the compass 535 to determine a predicted impact
point. In addition, the computer 532 may use the image metadata
from the UAV received from the RF receiver 542 or UAV remote video
terminal (RVT) 540, where the metadata may include the ground
position of the CFOV of the remote sensor, e.g., optical camera
(not shown), and may include the ground position of some or all of
the corners of the video image transmitted back to the system 500.
The fire control controller 532 may then use this metadata and the
predicted impact point to create an icon overlay 533 to be shown on
the display 520. This overlay 533 may include the positioning of
the CFOV and the predicted impact point B.
Exemplary embodiments of the fire control controller 532 may use
error inputs provided by the aforementioned connected components to
determine and show on the display 520 an error area (such as an
ellipse) about the predicted impact point. In one embodiment, the
fire control controller 532 may also transmit the predicted impact
GP 545 to the UAV via the RF transmitter 542 and its associated
antenna to direct the remote sensor on the UAV where to point and
capture images. In one embodiment, the fire control controller 532
may send a request to an intermediary where the request includes a
target point where the operator of the fire control controller 532
desires to view and requests to receive imagery from the sensor on
the UAV.
Additionally, in some embodiments, the fire control controller 532
may also include input from a map database 538 to determine the
predicted impact GP. Accuracy of the predicted impact GP may be
improved by use of map database in situations such as when the
weapon and the predicted impact GP are positioned at different
altitudes or ground heights. Another embodiment may include
environmental condition data 539 that may be received as input and
used by the fire control controller 532. The environmental
condition data 539 may include wind speeds, air density,
temperature, and the like. In at least one embodiment, the fire
control controller 532 may calculate round trajectory based on the
state estimate of the weapon, as provided by the IMU and
environmental conditions, such as wind estimate received from the
UAV.
FIG. 6 shows an embodiment of the weapon targeting system 600
having a weapon 610, for example, mortar, gun, or grenade launcher,
with a display or sight 620 which views a target area C about a
predicted impact GP B and centered on a CFOV D as viewed by an UAV
680 having a gimbaled camera 650. The UAV 680 includes a gimbaled
camera controller 670 that directs the camera 650 to the predicted
impact GP B received by the transmitter/receiver 660 from the
weapon 610. In one embodiment, the UAV may provide an
electro-optical (EO) and infrared (IR) full-motion video (EO/IR)
imagery with the CFOV. That is, the transmitter/receiver 660 may
send video from the sensor or camera 650 to the display 620. In
embodiments of the weapon targeting system there may be two options
for the interaction between the weapon and the remote sensor,
active control of the sensor or passive control of the sensor. In
an exemplary embodiment of the active control, the gun or weapon
position may control the sensor or camera where the camera slews to
put the CFOV on the impact site and further, the camera provides
controls for actual zooming functions. In the exemplary embodiment
of the passive control, the UAV operator may control the sensor or
camera and accordingly, the impact site may only appear when it is
within the field of view of the camera. In this passive control
embodiment, the zooming capabilities of the camera are not
available; however, compressed data received from the camera (or
other video processing) may be used for zooming effects.
In embodiments with active control, the operator of the weapon has
supervised control of the sensor. The targeting system sends the
predicted impact ground point (GP) coordinates to the remote sensor
controller (which may be done in any of a variety of message
formats, including as a Cursor on Target (CoT) message). The remote
sensor controller uses predicted impact GP as a command for the
CFOV for the camera. The remote sensor controller then centers the
camera on that predicted impact GP. In the case of an existing lag
time between when the weapon positioning and when the sensor slews
to center its view on the predicted impact point, the targeting
device, e.g., fire control controller, will gray out the reticle,
e.g., cross-hairs, on the displayed image until the CFOV is
actually aligned with the predicted impact GP and it will display
the predicted impact GP on the image as it moves toward the CFOV.
In some embodiments, the barrel orientation of a weapon may then
effect a change in the movement of the Center Field of View of the
UAV thereby allowing the operator of the weapon to quickly seek and
identify multiple targets at they appear on the impact sight
display 620.
FIG. 7 shows embodiments of the weapon targeting system where the
targeting system is configured to control the remote camera on the
UAV. The display 710 shows the predicted impact GP B to the left
and above the CFOV E in the center of the view. In the display 710
the camera is in the process of slewing towards the predicted
impact point GP. In the display 720 the predicted impact GP B is
now aligned with the CFOV E in the center of the view of the image.
The display 730 shows a situation when the predicted impact GP B is
outside of the field of view of the camera, namely above and left
of the image shown. In this case either the sensor or camera has
not yet slewed to view the GP B or it is not capable of doing so.
This may be due to factors such as limits in the tilt and/or roll
of the sensor gimbal mount. In one embodiment, the display 730
shows an arrow F, or other symbols, where the arrow may indicate
the direction toward the location of the predicted impact GP B.
This allows the user to obtain at least a general indication of
where he or she is aiming the weapon.
In embodiments with passive control, the weapon user may have view
of an image from the remote sensor, but has no control over the
remote sensor or the UAV or other means carrying the remote sensor.
The weapon user may see the imagery from the remote sensor,
including an overlay projected onto the image indicating where the
predicted impact GP is located. If the predicted impact GP is
outside the field of view of the camera, an arrow at the edge of
the image will indicate which direction the computed impact point
is relative to the image (such as is shown in the display 730). In
such embodiments the user may move the weapon to position the
predicted impact ground point within the view and/or may request
that the UAV operator to redirect the remote sensor and/or the UAV
to bring the predicted impact GP into view. In this embodiment, the
weapon user operating the system in the passive control mode may
have control of the zoom of the image to allow for the facilitating
of location and maneuvering of the predicted impact GP. It should
be noted that embodiment of passive control may be employed when
there is more than one weapon system using the same display
imagery, e.g., from the same remote camera, to direct the targeting
of each of the separate weapons. Since calculation of the predicted
impact point is done at the weapon, with the targeting system or
fire control computer, given the coordinates of the imagery (CFOV,
corners), the targeting system may generate the user display image
without needing to send any information to the remote sensor. That
is, in a passive mode there is no need to send the remote camera
the predicted impact GP as the remote sensor is never directed
towards that GP.
FIG. 8 shows displays of an embodiment of the weapon targeting
system with passive control sensor/UAV control. The display 810
shows the predicted impact GP B outside of the field of view of the
camera, namely above and left of the image shown. In this case
either the camera hasn't yet slewed to view the GP B or it is not
capable of doing so--due to factors such as limits in the tilt
and/or roll of the sensor gimbal mount. In one embodiment, the
display 810 shows an arrow E or other symbol, indicating the
direction to the location of the predicted impact GP B. This allows
the user to obtain at least a general indication of where he or she
is aiming the weapon. The display 820 shows the predicted impact GP
B to the left and below the CFOV. While the GP B may be moved
within the image of the display 820 by maneuvering the
weapon--since the remote sensor control is passive--the sensor may
not be directed to move the CFOV to align with the GP B. The
displays 830 and 840 show an embodiment where the user has control
over zooming of the camera, zoomed in and zoomed out,
respectfully.
FIG. 9 shows embodiments where the image from the remote sensor is
rotated or not rotated to the weapon user's perspective, namely the
orientation of the weapon. The display 910 shows the imagery
rotated to the orientation of the weapon and shows the predicted
impact GP B, the CFOV E and the weapon location G. The display 920
shows the imagery not rotated to the orientation of the weapon and
shows the predicted impact GP B, the CFOV E and the weapon location
G. In one embodiment of the passive mode, the display may still be
rotated to the orientation of the target to the weapon, i.e., not
where the weapon is pointed. In this case, the weapon location G
would still be at the bottom of the display, but the predicted
impact GP B would not be CFOV.
In some embodiments, the system may include either, or both,
multiple weapons and/or multiple remote sensors. Multiple weapon
embodiments have more than one weapon viewing the same imagery from
a single remote sensor with each weapon system displaying its own
predicted impact GP. In this manner, several weapons may be
coordinated to work together in targeting the same or different
targets. In these embodiments, one of the weapons may be in active
control of the remote sensor/UAV, with the others in passive mode.
Also, each targeting device of each weapon may provide to the UAV
its predicted impact GP and the remote sensor may then provide, to
all the targeting devices of all the weapons, each of the predicted
impact GPs of the weapons in its metadata. This way, with the
metadata for each of the targeting devices, the metadata may be
included in the overlay of each weapon display. This metadata may
include an identifier for the weapon and/or the weapon
location.
FIG. 10 depicts an exemplary embodiment of the weapon targeting
system that may include multiple weapons receiving imagery from one
remote sensor. The UAV 1002 may have a gimbaled camera 1004 that
views a target area with the image boundary 1006 and image corners
1008. The center of the image is a CFOV. The weapon 1010 has a
predicted impact GP 1014 as shown on the display 1012 with the
CFOV. The weapon 1020 may have a predicted impact GP 1024 as shown
on the display 1022 with the CFOV. The weapon 1030 may have a
predicted impact GP 1034 at the CFOV as shown on the display 1032.
The CFOV may then be aligned with the GP 1034 in embodiments where
the weapon 1030 is in an active control mode of the remote
sensor/UAV. The weapon 1040 has a predicted impact GP 1044 as shown
on the display 1042 with the CFOV. In embodiments where the
predicted impact GPs of each weapon are shared with the other
weapons, either via the UAV or directly, each weapon may display
the predicted impact GPs of the other weapons. In one embodiment,
an operator of the UAV 1002 may use the imagery received from the
gimbaled camera 1004 to determine which weapon, for example, of a
set of weapons 1010,1020,1030,1040, may be in the best position to
engage the target in view of their respective predicted impact GPs
1044.
In some embodiments, the most effective weapon may be utilized
based on the imagery received from one remote sensor and
optionally, a ballistic table associated with the rounds.
Accordingly, a dynamic environment may be created where different
weapons may be utilized for a target where the target and the
predicted impact GP are constantly in flux. The control may be
dynamically shifted between the gun operator, a UAV operator, and
or a control commander, where each operator may have been in charge
of a different aspect of the weapon targeting system. That is, the
control or command of a UAV or weapon may be dynamically shifted
from one operator to another. Additionally, the system may allow
for an automated command of the different weapons and allow for the
synchronization of multiple weapons based on the received imagery
and command controls from the sensor on the UAV.
In some embodiments, one weapon may utilize multiple remote
sensors, where the weapon display would automatically switch to
show the imagery from the remote sensor either showing the
predicted impact GP, or with the GP off screen, or with the GP on
multiple image feeds, to show the imagery closest to the predicted
impact GP. This embodiment utilizes the best view of the predicted
impact GP. Alternatively, with more than one remote sensor viewing
the predicted impact GP, the weapon user may switch between imagery
to be display or display each image feed on its display, e.g.,
side-by-side views.
FIG. 11 depicts a scenario where as the weapon 1102 is maneuvered
by the user, the predicted impact GP of the weapon passes through
different areas--as observed by separate remote sensors. The weapon
display may automatically switch to the imagery of the remote
sensor that the weapon's predicted GP is located within. With the
weapon's predicted impact GP 1110 within the viewed area 1112 of
the remote camera of UAV 1, the display may show the video image A
from UAV 1. Then as the weapon is maneuvered to the right, as
shown, with the weapon's predicted impact GP 1120 within the viewed
area 1122 of the remote camera of UAV 2, the display will show the
video image B from UAV 2. Lastly, as the weapon is further
maneuvered to the right, as shown, with the weapon's predicted
impact GP 1130 within the viewed area 1132 of the remote camera of
UAV 3, the display will show the video image C from UAV 3.
FIG. 12 illustrates an exemplary top level functional block diagram
of a computing device embodiment 1200. The exemplary operating
environment is shown as a computing device 1220, i.e., computer,
having a processor 1224, such as a central processing unit (CPU),
addressable memory 1227 such as a lookup table, e.g., an array, an
external device interface 1226, e.g., an optional universal serial
bus port and related processing, and/or an Ethernet port and
related processing, an output device interface 1223, e.g., web
browser, an application processing kernel 1222, and an optional
user interface 1229, e.g., an array of status lights, and one or
more toggle switches, and/or a display, and/or a keyboard,
joystick, trackball, or other position input device and/or a
pointer-mouse system and/or a touch screen. Optionally, the
addressable memory may, for example, be: flash memory, SSD, EPROM,
and/or a disk drive and/or another storage medium. These elements
may be in communication with one another via a data bus 1228. In an
operating system 1225, such as one supporting an optional web
browser and applications, the processor 1224 may be configured to
execute steps of a fire control controller in communication with:
an inertial measurement unit, the inertial measurement unit
configured to provide elevation data to the fire control
controller; a magnetic compass, the magnetic compass operable to
provide azimuth data to the fire control controller; a global
positioning system (GPS) unit, the GPS unit configured to provide
position data to the fire control controller; a data store, the
data store having ballistic information associated with a plurality
of weapons and associated rounds; and where the fire control
controller determines a predicted impact point of a selected weapon
and associated round based on the stored ballistic information, the
provided elevation data, the provided azimuth data, and the
provided position data. In one embodiment, a path clearance check
may be performed by the fire control controller where it provides
the ability to not fire a round if the system detects that there is
or will be an obstruction on the path of the weapon if fired.
It is contemplated that various combinations and/or
sub-combinations of the specific features and aspects of the above
embodiments may be made and still fall within the scope of the
invention. Accordingly, it should be understood that various
features and aspects of the disclosed embodiments may be combined
with or substituted for one another in order to form varying modes
of the disclosed invention. Further it is intended that the scope
of the present invention is herein disclosed by way of examples and
should not be limited by the particular disclosed embodiments
described above.
* * * * *
References